1. Field of the Invention
The present invention relates to an absorption type refrigerator, and more particularly to an absorption type refrigerator which has an improved heat-exchange efficiency and is compact and relatively inexpensive.
2. Background
Co-pending U.S. application Ser. No. 07/911,554 discloses a heat exchange device for an absorption type refrigerator, which includes a wave-like shape bellows-fin formed by consecutively bending a thin plate and seal plates attached to ends of the bellows-fin for sealingly separating chambers disposed on opposite sides of the bellows-fin. The present invention is directed to the use of this heat-exchange device as a (high-temperature) generator.
A conventional (high-temperature) generator is constructed as shown in FIGS. 6(a) and 6(b), where FIG. 6(a) is a cross-sectional view of the generator and FIG. 6(b) is a perspective view of an internal portion thereof. A furnace tube portion 19 and a smoke tube portion 20 are provided within a drum 18 and submerged in solution so as to function as heat transmitting tubes. The furnace tube portion 19 and the exhaust pipe portion 20 are connected at their ends to a tube plate by soldering or the like so as to communicate with each other. As shown in FIG. 6(b), the furnace tube portion 19 is provided at its one end with a burner 1 which mixes and burns the supplied fuel and air and moves the generated combustion gas from the furnace tube portion 19 through the exhaust pipe portion 20. The combustion gas is heat-exchanged with the solution through the heat transmitting tubes during the movement thereof, and thereafter discharged as an exhaust gas. On the other hand, the solution is introduced into the inside of the drum through a diluted solution inlet 3, generates refrigerant vapor through the heat-exchange with the combustion gas, is converted into medium concentration solution and is discharged from a medium concentration solution outlet 4. The generated refrigerant vapor is discharged from the refrigerant vapor outlet 5 provided in an upper portion of the drum.
However, a conventional (high-temperature) generator of the absorption type refrigerator has the following disadvantages. The generator cannot perform sufficient heat exchange since the liquid level is relatively high, above the top of the smoke pipe, making it difficult to boil the solution. Therefore, a large amount of solution is necessary, resulting in a high cost. Since the amount of the solution is relatively large, the heat quantity required for heating the solution must be increased, and therefore, the set-up or build-up time must be lengthened further increasing the cost. Further, since the heat is likely to be transmitted to the pipe plate, the soldering portion between the furnace tube and the smoke pipe must be increased in strength against the thermal stress applied thereto. Therefore, the furnace tube and the smoke pipe must be relatively thick, resulting in yet additional costs. In view of the assembling process employing the soldering process, it is difficult to reduce the size of the generator.
The present invention was made in order to solve the problems mentioned above. An object of the present invention is to provide an absorption type refrigerator in which a (high-temperature) generator has an improved heat-exchange efficiency and is relatively compact and inexpensive.